The "collaborative clinical diabetes trial (RFA NIAMDD 81-01) on the relationship between blood glucose control and vascular complications of insulin-dependent diabetes mellitus" seeks "to determine whether strict control of blood glucose concentration is effective in preventing or ameliorating the vascular complications of insulin-dependent diabetes mellitus." The University of Iowa Hospitals and Clinics is seeking to become a clinical center based upon the following experience and capabilities: 1) there is an established basic research facility in diabetes, the Diabetes and Endocrine Research Center, 2) there is a proven record of clinical research, 3) there is a modern clinical research center, 4) there will be a Diabetes Teaching Ward, 5) there are insulin pump studies in progress, 6) diabetic patients willingly participate in research protocols, 7) the presence of a stable clinical population, 8) an established record in Clinical Trials management, 9) a proven research and clinical interest in adherence to drug regimens, 10) and experience in the management of complicated dietary regimens. We believe this combination of circumstances at Iowa will permit the successful completion of the proposed Diabetes Trial.